The expansion in photocure-based additive manufacturing has been stunning and it represents a rare, truly disruptive technological advancement. The ability to rapidly produce customized models and functional parts to at least some degree, as well as enabling the transition toward digital rather than physical inventories is incredibly attractive. However, full realization of the potential promises of 3D printing is reliant on the sustained improvement in the materials and the processes used. There is a significant gap in the accessible performance spectrum of 3D printed parts where final material properties can be achieved that combine both high modulus/strength and high toughness. We are seeking to deliver a step-change in the performance potential of 3D printable materials in terms of robust, isotopic mechanical properties, greatly enhanced resolution and printing accuracy. Additional aspects deal with improved characterization of 3D printed materials that can apply to both existing formulations and particularly to highlight how the proposed lack of monomer migration into and within parts as they are being printed affects the final properties obtained. There are two specific Aims guiding this project. The first Aim involves the complementary coupling of two proven innovative approaches developed independently by the PI: 1) extremely high strength and high toughness photopolymers that match or even exceed the mechanical performance properties of engineering plastics that cannot be photo-processed in combination with 2) reactive nanogel additives that contribute significant network-like structure ahead of polymerization and the unique potential for continued post cure that remains spatially isolated only within the photo-exposed regions to yield extremely high resolution patterned structures. These features when combined, address several of the current limitations associated with 3D printing. The second Aim uses sophisticated analytical tools and models as well as printing and post-printing processes that will extend understanding of the complexities of photopolymer-based 3D printing. Our goal is to provide access to markedly higher performance and high resolution 3D printing materials that open opportunities for practical in-lab or even in-office production of fully functional printed crowns, bridges, dentures, and other intraoral prosthetics. These materials would also enhance the already growing dental market for orthodontic aligners, bite splints and even for higher resolution dental models while undoubtedly opening additional application areas not currently available due to an unmet need for higher performance materials. We can demonstrate that our baseline materials significantly outperform conventional dental materials and current 3D printed products. Providing a practical solution to the existing challenges that are impeding the logical transition of digital dentistry into printer-based clinical services, is the basis for this proposed project. The advances made here are also expected to resonate throughout the multitude of application areas that are becoming increasingly reliant on 3D printing as the performance of available materials improve.